A literature review on the improvement strategies of passive design for the roofing system of the modern house in a hot and humid climate region

Increase of indoor temperature compared with outdoor temperature is a major concern in modern house design.Occupants suffer from this uncomfortable condition because of overheating indoor temperature.Poor passive design causes heat to be trapped, which influences the rise in indoor temperature.The upper part, which covers the area of the roof, is the most critical part of the house that is exposed to heat caused by high solar radiation and high emissivity levels.During daytime, the roof accumulates heat, which increases the indoor temperature and affects the comfort level of the occupants.To maintain the indoor temperature within the comfort level, most house designs usually depend on mechanical means by using fans or air conditioning systems.The dependence on a mechanical ventilation system could lead to additional costs for its installation, operation, and maintenance. Thus, this study concentrates on reviews on passive design and suggests recommendations for future developments.New proposals or strategies are proposed to improve the current passive design through ventilated and cool roof systems. It is possible to achieve the comfort level inside a house throughout the day by reducing the transmitted heat into the indoor environment and eliminating the internal hot air.These recommendations could become attractive strategies in providing a comfortable indoor temperature to the occupants as well as in minimizing energy consumption

Study on the Optimum Roof Type with 30° Roof Angle to Enhance Natural Ventilation and Air Circulation of a Passive Design

One of the major problems in modern housing design is overheating. Occupants suffer higher indoor temperatures due to a lack of natural ventilation. This issue arises because of poor passive design. A good passive design promotes natural ventilation and provides better indoor air temperatures without reliance on mechanical cooling systems. The roofing system plays an important role in a house’s design. Since the roof contributes to 70% of the total heat gain, it is important to investigate its design to reduce the impact of overheating. It has been found that many roofs lack a ventilation system in the top part of the house. These openings in the roof provide areas for trapped hot air to exit into the environment. The openings also enhance natural ventilation and allow for effective air circulation inside the house. The optimum roof is designed to tackle this matter by reducing the overheating inside the house, especially during the hottest hours of the day. The hot air exits based on the differences in air density and due to prevailing wind. In this study, the optimum roof was tested on a small-scale model and verified by simulation using computational fluid dynamic (CFD) software, namely ANSYS 18.0. From the data obtained, it was proven that the opening in the roof reduced the indoor temperature. In conclusion, the optimum roof could improve the passive design and help to reduce overheating inside a house

Study On The Optimum Roof Type With 30° Roof Angle To Enhance Natural Ventilation And Air Circulation Of A Passive Design

One of the major problems in modern housing design is overheating. Occupants suffer higher indoor temperatures due to a lack of natural ventilation. This issue arises because of poor passive design. A good passive design promotes natural ventilation and provides better indoor air temperatures without reliance on mechanical cooling systems. The roofing system plays an important role in a house’s design. Since the roof contributes to 70% of the total heat gain, it is important to investigate its design to reduce the impact of overheating. It has been found that many roofs lack a ventilation system in the top part of the house. These openings in the roof provide areas for trapped hot air to exit into the environment. The openings also enhance natural ventilation and allow for effective air circulation inside the house. The optimum roof is designed to tackle this matter by reducing the overheating inside the house, especially during the hottest hours of the day. The hot air exits based on the differences in air density and due to prevailing wind. In this study, the optimum roof was tested on a small-scale model and verified by simulation using computational fluid dynamic (CFD) software, namely ANSYS 18.0. From the data obtained, it was proven that the opening in the roof reduced the indoor temperature. In conclusion, the optimum roof could improve the passive design and help to reduce overheating inside a house

Ventilated Roof for Modern Low-cost House in Hot Humid Climate

The overheating of indoor air temperature is one of the major concerns in a modern house design especially for the low-cost housing. Most of the occupants will feel uncomfortable when the indoor temperature is exceeding the level of thermal comfort. This result of the need to use mechanical means to cool the house, hence it surely incurs additional living cost to pay the electricity bill and maintenance cost. The overheating is a result from the hot air that trap in the house and the cause is due to poor of passive design; lack of ventilation provision in house design. It is important to remove the hot air from internal area to avoid any unforeseen event that could harm one’s health; to avoid heat stroke from happening. To overcome this problem, the proposed ventilated roof is introduced and designed with more openings on the roof surface areas. This research was conducted and carried out to investigate the effect of openings on the roof surface towards the indoor temperature of a house in tropical climate areas. For this study, on-site experiment was conducted by building model houses with common roof and ventilated roof design under fully closed and fully opened condition. Air temperature and air velocity were recorded and the data was used as an input to the CFD Simulation. The CFD simulation was carried out for validation purposes. Once validated, the CFD simulation was proceeded with model house with different pitch of roof. The CFD simulation on Betong’s house was conducted with ventilated roof tiles design. From the findings, it was concluded that model house with ventilated roof tiles design recorded lower indoor temperature as compared to common roof. In conclusion, the passive design of modern house is improved through the adoption of the ventilated roof tiles design, which it enhances the removal of the hot air and reduce air temperature inside the house. Keywords: Passive design; ventilated roof; CFD simulatio

A literature review on the improvement strategies of passive design for the roofing system of the modern house in a hot and humid climate region

Increase of indoor temperature compared with outdoor temperature is a major concern in modern house design. Occupants suffer from this uncomfortable condition because of overheating indoor temperature. Poor passive design causes heat to be trapped, which influences the rise in indoor temperature. The upper part, which covers the area of the roof, is the most critical part of the house that is exposed to heat caused by high solar radiation and high emissivity levels. During daytime, the roof accumulates heat, which increases the indoor temperature and affects the comfort level of the occupants. To maintain the indoor temperature within the comfort level, most house designs usually depend on mechanical means by using fans or air conditioning systems. The dependence on a mechanical ventilation system could lead to additional costs for its installation, operation, and maintenance. Thus, this study concentrates on reviews on passive design and suggests recommendations for future developments. New proposals or strategies are proposed to improve the current passive design through ventilated and cool roof systems. It is possible to achieve the comfort level inside a house throughout the day by reducing the transmitted heat into the indoor environment and eliminating the internal hot air. These recommendations could become attractive strategies in providing a comfortable indoor temperature to the occupants as well as in minimizing energy consumption